Demulsifier composition



Patented Dec. 27, 1949 UNITED STATES e TENT OFFICE 6f Texas No' Drawing. ApplicationgNov em'ber 194i,

Serial N0. 785,549

, '3 Claims. 1

This invention relates to the treatment of emulsions of mineral oil and water, such as petroleum emulsions, for the purposeof separating the oil from the water.

An object of this invention is to provide -a novel {process for breaking or separating petroleum emulsions by subjecting such emulsions to the action of a novel demuls'ifying composition to be described in greater detail hereinafter.

Another object is the provision of a novel de- .mulsifier which is highly effective for breaking or separating petroleum emulsions.

The new demulsifler in accordance with this invention comprises a physical mixture composed of a water-soluble mahogany soap derived from petroleum, an oxidized tatty body,- and a compound comprising a :polyoxyalkylene derivative of -a hexahyd-ric body which has been partially 'es terified with a long-chain fatty acid- I The water-soluble mahogany soaps are well known, commercially available, materials which are derived from petroleum distillates during-conventional treatmentthereof with sulfuric acid, the soaps being most often prepared in the form of the ammonium, sodium or potassium salts of the mahogany acids. In the composition in accordance with this invention, the acids employed are those ranging in molecular weight from about 250-504) and preferably those of about 425 molecular weight. The sodium soaps, particularly, of these acids are viscous fluids, reddish-amber to brown in color and readily miscible with the other components of the 'demulsify-i-ng composition contemplated by this invention.

The oxidized fatty bodies employed may be characterized as the oxidized derivatives of the unsaturated fattyoi-ls or acids. These include the various blown oils, '(or their fatty acids) such as blown castor, rapeseed, soya, sesame, fish oils, oleins, and many others derived from vegetable, animal or marine sources. These blown or oxidized fatty oils or fatty acids may be used singly or mixtures of two or more of them may be successfully employed in the composition in accordance with this invention. Cost will normally be the determining factor in theselection of the particular oxidized material which is employed.

The third principal comparator the new composition may be characterized as a polyoxyalkylene derivative of a hexahydric body which has been partially esterfied with a long chain fatty acid. Mire specifically these materials are derived from the various hex-a-hyd-ric alcohols, such as mannito'l, sorbitol, and dul'oitol, and their anhydrides, which include the sorbitans, sorbides,

mannitans and mannides. These hexahydric al 'co'hols o'r anhydrides are partially es'ter'fied with long 'chain fatty acids, such as oleic, palmitic, steariqand lauric acids to provide partial esters having several free hydroxyl groups on the polyh'ydric body. These free hydroxyls are then fur'-' ther modified by reaction with alkylene oxide to produce a final compound having both free 'hydroxyl and ether oxygen subs'tituents which provide the compound with desirable surface active, hydrophilic characteristics. These materials are 'commerciallyavailable under the trade "name of Tweens and their physical and chemical cha-r "acftr'istics are described in a pamphlet, entitled Atlas spans and 'Atlas Tweeii's, reissued June, 1945 by the Atlas Powder Com any of Wilming ton, Delaware. I

In addition to the adore-described principal components of the composition in accordance With'this invehti'oh, a quantity o f'a sultable thinning agent is usually added. These agents include such materials asethyl alcohol, isopropyl alcohol, p'e'trolui'n naphtha. solvent naphthas derived from coal and wood tar and other similar hydrocarbon solvents conventionally used for' thinning demulsifying compounds.

Also, the final product may include a suitable agent for neutralizing or saponifying any free acids in the principal composition. Such agents may include the alkali hydroxides, ammonia, or the various basicamines, some examples of which are the mono-, di-, and tri-ethanolamines and their equivalents.

Following are several examples of the method of manufacturing compositions in accordance with this invention.

Example '1 200 pounds of water-soluble mahogany acids of about 425 molecular weight, in the form of the sodium salt, 113 pounds of commercial heavybodies castor oil, and 25 pounds of commercial blown soyabean oil are run into a steam jacketed kettle where these materials are heated to about 150 F. and stirred until a homogeneous mixture is obtained. The temperature employed is only such as is necessary to thin the materials sufiiciently to permit easy stirring and thorough mixing of the ingredients, as no chemical reaction between the mixed materials is sought or is necessary. About 16 pounds of Tween 80 is i then added to the kettle mixture and stirred Emampte 2 To the composition in accordance with Example 1, sufficient strong ammonia -(27 B-.) Was added to neutralize any free acidity in the composition. In the case of the Example 1 material, about 2% by weight of the ammonia was suflicient for this purpose. The ammonia is preferably added to the kettle mixture of mahogan soap and. blown oils before the addition of the Tween 80 and the thinner. After suitable stirring to complete the neutralization reaction, the Tween 80 is added and thoroughly mixed with the neutralized material, following which, a suitable amount of thinner is added to produce the final demulsifier composition.

Exclusive of the thinner, a typical composition will contain about 85 to 97% of a mixture of mahogany soaps and blown fatty bodies, the relative proportions of these two materials varying from 30-70% of either one or the other. The quantity of Tween 80 will range from 3 to 15% in the mixture of primary components.

This mixture of primary ingredients may be thinned by from about 15 to 40% of thinner, depending primarily upon the nature of the emulsion to be treated and the treating conditions employed.

A typical final composition in accordance with Example 1 above will contain the several ingredients in approximately the following weight proportions:

Per cent Water soluble mahogany soap 45 Heavy bodied castor oil M 25 Blown soya bean oil 5 Tween 80 4 Thinner 21 A typical composition of the Example 2 type will contain the same ingredients, modified as to proportions to include about 2% b weight of 27 B, ammonia.

In practicing the process, a treating agent or demulsifying agent of the kind above described may be brought in contact with the emulsion to be treated in any of the numerous ways now employed in the treatment of petroleum emulsions with chemical demulsifying agents, such, for example, as by introducing the treating agent into the well in which the emulsion is produced, introducing the treating agent into a conduit through which the emulsion is flowing, introducing the treating agent into a tank in which-the emulsion is stored, or introducing the treating agent into a container that holds a sludge obtained from the bottom of an oil storage tank. In some instances, it may be advisable to introduce the treating agent into a producing well in such a way that it will become mixed with water and oil that are emerging from the surrounding strata, before said water and oil enter the barrel of the well pump or the tubing up through which said water and oil flow to the surface of the ground. After treatment the emulsion is allowed to stand in a quiescent state, usually in a settling tank, at a temperature varying from atmospheric temperature to about 200 F., so as to permit the water or brine to separate from the oil, it being preferable to keep the temperature low enough so as to prevent the valuable constituents of the oil from volatilizing. If desired, the treated emulsion may be acted upon by one or the other of various kinds of apparatus now used in the operation of breaking petroleum emulsions, such as 'homogenizers, hay tanks, gun barrels, filters, cen- "trifuges, or electrical dehydrators.

The amount of treating agent on the anhydrous basis that is required to break the emulsion may vary from approximately 1 part of treating agent to 500 parts of emulsion, up to a ratio of 1 part of treating agent to 20,000 parts of emulsion, depending upon the type or kind of emulsion being'treated. In treating exceptionally refractory emulsions of the kind commonly referred to as tank bottoms or residual pit oils, the minimum ratio above referred to is often necessary, but in treating fresh emulsions, i. e., emulsions that will yield readily to the action of chemical delnulsifying agents, the maximum ratio above mentioned will frequently produce highly satisfactory results. For the average petroleum emulsion of the water-in-oil type a ratio of 1 part of treating agent to 10,000 parts of emulsion will usually be found to produce commercially satisfactory results. 7

What I claim and desire to secure by Letters Patent is:

1. A demulsifier composition for breaking water-inoil petroleum emulsions consisting essentially of 15 to 3% of a polyoxyalkylene derivative of a hexahydric body partially esterified with a long chain fatty acid, and 85 to 97% of a mix ture of water-soluble mahogany soap and an oxidized unsaturated fatty body selected from the group consisting of the unsaturated fatty oils and fatty acids, said fatty body comprising 30 to of said mixture.

2. A demulsifier composition for breaking water-in-oil petroleum emulsions consisting essentiallly of 15 to 3% of a polyoxyalkylene detrivative of sorbitan mono-oleate, and to 97% of a mixture of water-soluble mahogany soap and an oxidized unsaturated fatty body selected from the group consisting of the unsaturated fatty oils and fatty acids, said fatty body comprising 30 to 70% of said mixture.

3. A demulsifier composition for breaking water-in-oil petroleum emulsions consisting essentially of water-soluble mahogany soap 58 to 16%; oxidized unsaturated fatty oils 24.5 to 36.5%; polyoxyalkylene derivative of sorbitan monooleate 2.5 to 7.5%; and hydrocarbon solvent 15 to 40%.

FRITZ E. FUCHS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,668,941 Burgess May 8, 1928 1,940,394 De Groote et al Dec. 19, 1933 1,984,633 De Groote et a1. Dec. 18, 1934 2,115,843 Dawson May 3, 1938 2,209,445 Mering 'July 30, 1940 

